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Thursday, January 21, 2016

Do Bridges Leak? Natural Gas Sure Does – Just Ask California…

By Andrea Lang, Energy Fellow

Last week, I wrote about why Oregonians should be wary of shifting away from coal by
investing in more natural gas infrastructure to power our electric grid.
Besides the fact that such infrastructure would be in place for years and thus is unlikely to be a “bridge” to renewable energy, it is not necessarily
less carbon intensive than other fossil fuels. While burning natural gas results in less CO2 emissions than coal, there are also lots of methane leakages during
natural gas production, storage, and transportation. And since methane is 25-37 times more potent (it depends on the timeframe considered) as a
greenhouse gas than CO2, these leakages are significant.The ongoing methane leak in California, along
with numerous other leaks across the country, illustrates the hidden climate
cost of natural gas.

A methane leak in Porter Ranch,
California has already leaked more than 86,000 metric tons of methane, or the
equivalent of more than seven million metric tons of CO2. That leak
is expected to continue at least into late February or March. In the
meantime, you can watch the methane emissions go up in real time on a methane counter created by the Environmental Defense Fund. The leak has caused
California’s governor to declare a state of emergency in the area, and has resulted in thousands of
evacuations. But in addition to the local impacts of the leak, it highlights
one of the major problems with natural gas in terms of global climate impacts.
Though invisible to the eye, the leak in California is currently the daily equivalent of driving seven million cars.

The California methane leak is by no means an
isolated incident. A recent study concluded that for natural gas to produce more
climate-friendly electricity than coal, leakage must be kept below 3.2%.
However, there is a lot of uncertainty about how much leakage is actually
occurring from natural gas infrastructure and whether it is in fact below that
3.2% threshold. Although the EPA has estimated that leakage rates are well
under the threshold, numerous studies (see here, here, and here) have
concluded that EPA may be drastically underestimating methane leakage.

Chances are, even with all of
these leaked emissions, natural gas is still cleaner than coal. But the scary
part (aside from the terrible local impacts of large-scale leakages like the
one in California) is that nobody is totally sure about how much fugitive
emissions really occur. And with natural gas being touted as the “bridge” to a
renewable and sustainable energy future, it seems like a big risk to take. In
the transition away from coal, we would be much better served by investing in
truly green infrastructure, increasing the percent of electricity from solar,
wind, and other renewable energy sources.